One-needle knit fabric is made using a single needle bed that create loops in one linear orientation, resulting in a fabric with clearly differentiated front and back surfaces. The front side typically shows a clean, uniform appearance with V-knit patterns, while the reverse appears irregular and nubby. This construction makes single-knit fabrics lightweight and stretchy, but they also tend to fold inward at the borders and can unravel quickly if a single loop is broken. Single knits are commonly used in athletic wear, activewear, OEM Men's sweater sweater and snug apparel where comfort and flexibility are important.

Two-needle knit fabric, on the other hand, is created using two sets of needles that create mirrored stitch structures on both surfaces. This results in a fabric that has no discernible right or wrong side, with a more stable and dense structure. Because the loops are mutually anchored, double-knit fabrics are less likely to curl at the edges and are far less prone to unraveling. They also have less stretch than single knits, but they offer superior structure and longevity. Interlock materials are often used in structured apparel such as blazers, pencil skirts, and trousers where a defined silhouette and enhanced durability are desired.

In terms of thickness and weight, double-knit fabrics are generally heavier and warmer than single-knit fabrics due to their double layer construction. This makes them suitable for cooler weather or items meant to maintain their silhouette. Single knits are more air-permeable and better suited for warm climates or active wear where moisture wicking and flexibility are priorities.

The choice between one-needle and two-needle fabric depends on the purpose of the apparel. Jersey fabrics offer pliability and relaxed fit, while Two-needle knits provide structure, durability, and a more polished appearance. Both are essential in garment construction, and knowing their structural distinctions helps in selecting the right fabric for the right purpose.